Analysis

Victims By State

Nevada has had the most victims from mass shootings, due to the 2017 Las Vegas Strip massacre in which there were 604 victims (546 injured, and 58 killed).

Shootings By State

35 of the 50 states (70%) had at least one mass shooting between 1982 and 2019.

California has had the most mass shootings (19).

Shootings By Gender

96%

of mass shooters were men

Shootings By Year

The number of mass shootings per year in the US is increasing.

The year with the most shootings was 2018 which consisted of 11% of the mass shootings.

Shootings Per State Over Time

Shootings By Decade

The number of mass shootings this decade is almost triple the number in the previous decade.

Shootings By Decade & State

California and Texas have had mass shootings in every decade.

Shootings By Race

56% of mass shooters were white.

Prior Signs of Mental Health Issues

53% of mass shooters had prior signs of mental health issues.

Were Weapons Obtained Legally?

72% of mass shooters obtained weapons legally.

Shootings By Location Type

A third of US mass shootings occurred in a workplace.

Age Of Shooter

Shooter ages ranged from 11 to 66.

Age Bracket Of Shooter

A third of mass shooters were in their 20s (34% of mass shootings).

Year & Age Bracket

There is a noticeable increase in recent years in the number of mass shooters in their twenties.

Note: The age bracket “1-12” has been excluded from the charts because there was only one instance in that category and so there is little use trying to illustrate the pattern over time for that age bracket.

Semi-Automatic Weapons

Almost two thirds (65%) of mass shootings involved semi-automatic weapons.

Multiple Weapons

Just over half (53%) of mass shootings involved multiple weapons.

State & Semi-Automatic Weapons

State & Multiple Weapons

State & Race

State & Weapons Obtained Legally

State & Location Type

State & Prior Signs of Mental Health Issues

State & Age Bracket

Decade & Semi-Automatic Weapons

Decade & Multiple Weapons

Decade & Prior Signs of Mental Health Issues

Decade & Weapons Obtained Legally

Decade & Location Type

Semi-Automatic Weapons & Prior Signs of Mental Health Issues

Multiple Weapons & Prior Signs of Mental Health Issues

Multiple Weapons & Semi-Automatic Weapons

Semi-Automatic Weapons & Age Bracket

Weapons Obtained Legally & Age Bracket

Multiple Weapons & Age Bracket

Multiple Weapons & Weapons Obtained Legally

Semi-Automatic Weapons & Weapons Obtained Legally

Age Bracket & Prior Signs of Mental Health Issues

Location Type & Prior Signs of Mental Health Issues

Weapons Obtained Legally & Prior Signs of Mental Health Issues

Location Type & Age Bracket

Location Type & Semi Automatic Weapons

Location Type & Multiple Weapons

Location Type & Race

Age Bracket & Race

Data Cleanse

Gender

The original breakdown of number of mass shootings by gender was:

Gender Shootings
F 1
Female 2
M 36
Male 70
Male & Female 1

The cleansed breakdown is:

Gender Shootings
Female 3
Male 106
Male & Female 1

Race

The original breakdown of number of mass shootings by race was:

Race Shootings
1
- 2
Asian 8
black 9
Black 9
Latino 10
Native American 3
Other 5
unclear 1
white 41
White 21

The cleansed breakdown is:

Race Shootings
Black 18
Latino 10
Native American 3
Unknown 17
White 62

Weapons Obtained Legally

The original breakdown of number of mass shootings by “Weapons Obtained Legally” was:

Weapons Obtained Legally Shootings
Yes 2
- 1
Kelley passed federal criminal background checks; the US Air Force failed to provide information on his criminal history to the FBI 1
No 16
TBD 7
Unknown 6
Yes 76
Yes (“some of the weapons were purchased legally and some of them may not have been”) 1

The cleansed breakdown is:

Weapons Obtained Legally Shootings
No 16
Unknown 15
Yes 79

State

A new column was added containing the state code e.g. CA for California.

In the original data, the unique states after the comma in the location column were:

State Shootings
Arizona 1
Arkansas 1
CA 5
California 14
CO 1
Colorado 5
Connecticut 3
D.C. 1
FL 2
Florida 9
Georgia 2
Hawaii 1
IL 2
Illinois 2
Iowa 1
Kansas 1
Kentucky 2
Lousiana 1
Massachusetts 1
MD 3
Michigan 2
Minnesota 2
Mississippi 1
Missouri 1
Nebraska 1
Nevada 1
New York 4
North Carolina 2
NV 1
OH 1
Ohio 2
Oklahoma 1
Oregon 2
PA 3
Pennsylvania 2
South Carolina 2
Tennessee 1
Texas 7
TN 1
TX 2
Utah 1
Virginia 1
Washington 7
Wisconsin 4

After cleansing, the unique states are:

State Shootings
AR 1
AZ 1
CA 19
CO 6
CT 3
D.C. 1
FL 11
GA 2
HI 1
IA 1
IL 4
KS 1
KY 2
LA 1
MA 1
MD 3
MI 2
MN 2
MO 1
MS 1
NC 2
NE 1
NV 2
NY 4
OH 3
OK 1
OR 2
PA 5
SC 2
TN 2
TX 9
UT 1
VA 1
WA 7
WI 4

Location Type

The location types were:

Location Type Shootings
Workplace 1
Airport 1
Military 5
Other 42
Other 3
Religious 6
School 17
Workplace 35

There were 2 instances of “Workplace”" as one had a leading white space.

There were also 2 instaces of “Other”" as one with a trailing white space.

The cleansed types are:

Location Type Shootings
Airport 1
Military 5
Other 45
Religious 6
School 17
Workplace 36

Prior Signs Of Mental Health Issues

The values in the imported data were:

Prior Signs Of Mental Health Issues Shootings
- 7
No 17
TBD 3
Unclear 24
Unknown 1
Yes 58

The values are now:

Prior Signs Of Mental Health Issues Shootings
No 17
Unknown 35
Yes 58